Bolt hard to pull back

[Cookie91/38]

Hello,

Ive been reloading 308 for about a month or two now, and i just made a few batches with 175SMK's. I trim the brass to 2.008, and the OAL Is 2.8 with the SMK. When I close the bolt its smooth, but about 50% of the time the bolt lifts up easily, but "locks up" and you really have to tug at it to pull it back. Im getting great groupings, but was wondering what is causing this? And my weapon is a remington 700 sps tactical with a usually very smooth bolt. Thanks a lot, Evan

[Ahhnother8]

Overpressure OR brass fired in another gun needs to be small-base sized one time only, then will work fine in this gun.

[Cookie91/38]

This brass has only been fired in this gun. It is PPU brass. My load is 42.2 so I don't think overpressure would be an issue? It was doing this with a 41.7 load too

[noylj]

If the brass goes in easily, it should come out easily, unless you are over pressure—assuming the bolt can be easily pulled back with factory ammo.
Does this happen with factory loads?
What powder are you using?
Did you work up the load from the start load and did the start loads extract easily?
I hope you aren't just jumping into what you THINK is a safe load.
This used to be the way rifle loads were all tested—until hard bolt lift or sticky extraction and then charge weight was reduced by 0.5-1.0gn. Many of these pet loads were found to be running about 70-75,000 psi (after dropping the 0.5-1.0gn) and had been used for decades.
Any marks/shiny areas on the case heads?
If not over pressure, then possibly improper annealing has weakened the whole case or there is a problem with your bolt (improper heat treating or such).
You can try to cover the whole case with black Magic Marker, fire the round, and, upon extraction, see where the "hang up" is.
Your manual may say it is a safe load, but your rifle is telling you it is over-pressure.

[Cookie91/38]

Yes factory rounds go in and out easily. Im using 4046 powder, and I started out at 41.7. Ill look when I can for any marks on the case heads. If they were over pressured, wouldn't all the rounds be sticking? Or can it vary? Because some ejected smooth and some didn't.

[noylj]

I show 41.3gn of 4064 as max and 34.0gn being start. I see references to 4046 on the 'net, but I don't show it in any reloading manual or on the IMR site.
Load some at 34gn and work up and see if there is some sticking at all loads or if it suddenly appears at some charge weight. Could be some bad cases, could be high pressure in YOUR rifle (small match chamber or such that doesn't apply to the test barrel used by the manual's test lab).
Call Remington and discuss it with them.

[rsrocket1]

As mentioned, take one of your "really tight" fired brass cases and color it with a magic marker. Try and chamber it again and look for where the ink rubs. It will probably be on the shoulder which means you need to bump it back a couple of mils. If you neck size only, every few firings you may need to bump the shoulder back a little.

You can do a "partial full length resize" by starting with a full length dies and screwing it out a couple of turns from touching the shell holder. Then screw it in until it pushes the shoulder back to where the shoulder will no longer rub the chamber of your rifle. Mark the spots on the die and retaining nut so you can reference the spot in the future when you have some more cases that need the shoulder bumped back.

A headspace gauge can tell you whether you need to bump.

[Cookie91/38]

As mentioned, take one of your "really tight" fired brass cases and color it with a magic marker. Try and chamber it again and look for where the ink rubs. It will probably be on the shoulder which means you need to bump it back a couple of mils. If you neck size only, every few firings you may need to bump the shoulder back a little.

You can do a "partial full length resize" by starting with a full length dies and screwing it out a couple of turns from touching the shell holder. Then screw it in until it pushes the shoulder back to where the shoulder will no longer rub the chamber of your rifle. Mark the spots on the die and retaining nut so you can reference the spot in the future when you have some more cases that need the shoulder bumped back.

A headspace gauge can tell you whether you need to bump.

I actually full length resize every time right now, so does this still apply?

[jdmstuff]

I show 41.3gn of 4064 as max and 34.0gn being start. I see references to 4046 on the 'net, but I don't show it in any reloading manual or on the IMR site.
Load some at 34gn and work up and see if there is some sticking at all loads or if it suddenly appears at some charge weight. Could be some bad cases, could be high pressure in YOUR rifle (small match chamber or such that doesn't apply to the test barrel used by the manual's test lab).
Call Remington and discuss it with them.

Where are you getting your load data from? The Hodgdon site shows the starting load at 41.5 with a max at 45.6 compressed.

[rsrocket1]

I actually full length resize every time right now, so does this still apply?

No, if you full length resize you should not have a headspace problem unless your die is not screwed down all the way and you cannot slip a piece of paper between the die and the shell holder with a case being resized. I've read of folks thinking they are fully resizing their brass only to find out that they were short stroking the press or that they didn't check that the die touched the shellplate with the case in the die, only without the case.


I would still try the magic marker test to see where the cases are binding in your chamber.

[Cookie91/38]

No, if you full length resize you should not have a headspace problem unless your die is not screwed down all the way and you cannot slip a piece of paper between the die and the shell holder with a case being resized. I've read of folks thinking they are fully resizing their brass only to find out that they were short stroking the press or that they didn't check that the die touched the shellplate with the case in the die, only without the case.


I would still try the magic marker test to see where the cases are binding in your chamber.

Il try the magic marker thing in a bit here. So should the die not touch the shell plate?

[noylj]

Ah, yes, and your source is more accurate than my source. My source was Hornady.
Remember, no lab has your gun, your exact lot number of bullets, or your exact lot numbers of powder or primers, and probably not your brand or lot number of cases. A manual is a guideline only.
Believe me, a start load in one manual can be max or over max in another or in your gun.
This is why I start at the lowest starting load I can find (referencing several sources) and work up looking for pressure signs (with hard extraction at the top of the list).
Call Hodgdon or Rem and ask them what they think.
If your sizing die is NOT screwed down all the way, you may not be able to chamber the case, but the head space would not be problem (with the case pushed all the way forward, there would not be excessive space between the case head and the breech, which to me is excessive head space). Head space issues, to me, come from pushing the shoulder back too far. Thus, I screw the sizing die down just until the cases easily chamber.

[Cookie91/38]

Ah, yes, and your source is more accurate than my source. My source was Hornady.
Remember, no lab has your gun, your exact lot number of bullets, or your exact lot numbers of powder or primers, and probably not your brand or lot number of cases. A manual is a guideline only.
Believe me, a start load in one manual can be max or over max in another or in your gun.
This is why I start at the lowest starting load I can find (referencing several sources) and work up looking for pressure signs (with hard extraction at the top of the list).
Call Hodgdon or Rem and ask them what they think.
If your sizing die is NOT screwed down all the way, you may not be able to chamber the case, but the head space would not be problem (with the case pushed all the way forward, there would not be excessive space between the case head and the breech, which to me is excessive head space). Head space issues, to me, come from pushing the shoulder back too far. Thus, I screw the sizing die down just until the cases easily chamber.

I screw the sizer die down until it touches the shell plate, per the instructions in the manual. I guess Il reduce my load down a few grains and see what happens?

[maxx03]

I screw the sizer die down until it touches the shell plate, per the instructions in the manual. I guess Il reduce my load down a few grains and see what happens?

The shoulder might need to get bumped back a little more. Screw the die in 1/8 to 1/4 turn so it cams over when you're at the top of the press stroke.

[Divernhunter]

Sounds like you are just on the edge. Drop the charge 1 gr and try it.
Also if you are using a single stage press screw the die down until it touches THEN 1/4 more turn and lock it. The handle should cam-over when there is no shell in the press. It is easier to feel without a shell in the press.